From a55039df84f53a4a3060e2a7ae84dee1dc9006ef Mon Sep 17 00:00:00 2001
From: Yoshua Wuyts <yoshuawuyts@gmail.com>
Date: Sun, 22 Nov 2020 01:04:02 +0100
Subject: [PATCH 1/2] Stabilize Arc::{incr,decr}_strong_count

---
 library/alloc/src/sync.rs | 18 +++++++-----------
 library/alloc/src/task.rs |  4 ++--
 2 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/library/alloc/src/sync.rs b/library/alloc/src/sync.rs
index 9d478a302e96c..1ff30ca610dbb 100644
--- a/library/alloc/src/sync.rs
+++ b/library/alloc/src/sync.rs
@@ -870,15 +870,13 @@ impl<T: ?Sized> Arc<T> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(arc_mutate_strong_count)]
-    ///
     /// use std::sync::Arc;
     ///
     /// let five = Arc::new(5);
     ///
     /// unsafe {
     ///     let ptr = Arc::into_raw(five);
-    ///     Arc::incr_strong_count(ptr);
+    ///     Arc::increment_strong_count(ptr);
     ///
     ///     // This assertion is deterministic because we haven't shared
     ///     // the `Arc` between threads.
@@ -887,8 +885,8 @@ impl<T: ?Sized> Arc<T> {
     /// }
     /// ```
     #[inline]
-    #[unstable(feature = "arc_mutate_strong_count", issue = "71983")]
-    pub unsafe fn incr_strong_count(ptr: *const T) {
+    #[stable(feature = "arc_mutate_strong_count", since = "1.50.0")]
+    pub unsafe fn increment_strong_count(ptr: *const T) {
         // Retain Arc, but don't touch refcount by wrapping in ManuallyDrop
         let arc = unsafe { mem::ManuallyDrop::new(Arc::<T>::from_raw(ptr)) };
         // Now increase refcount, but don't drop new refcount either
@@ -909,27 +907,25 @@ impl<T: ?Sized> Arc<T> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(arc_mutate_strong_count)]
-    ///
     /// use std::sync::Arc;
     ///
     /// let five = Arc::new(5);
     ///
     /// unsafe {
     ///     let ptr = Arc::into_raw(five);
-    ///     Arc::incr_strong_count(ptr);
+    ///     Arc::increment_strong_count(ptr);
     ///
     ///     // Those assertions are deterministic because we haven't shared
     ///     // the `Arc` between threads.
     ///     let five = Arc::from_raw(ptr);
     ///     assert_eq!(2, Arc::strong_count(&five));
-    ///     Arc::decr_strong_count(ptr);
+    ///     Arc::decrement_strong_count(ptr);
     ///     assert_eq!(1, Arc::strong_count(&five));
     /// }
     /// ```
     #[inline]
-    #[unstable(feature = "arc_mutate_strong_count", issue = "71983")]
-    pub unsafe fn decr_strong_count(ptr: *const T) {
+    #[stable(feature = "arc_mutate_strong_count", since = "1.50.0")]
+    pub unsafe fn decrement_strong_count(ptr: *const T) {
         unsafe { mem::drop(Arc::from_raw(ptr)) };
     }
 
diff --git a/library/alloc/src/task.rs b/library/alloc/src/task.rs
index fcab3fd0badce..4ee79dae3f1a3 100644
--- a/library/alloc/src/task.rs
+++ b/library/alloc/src/task.rs
@@ -60,7 +60,7 @@ impl<W: Wake + Send + Sync + 'static> From<Arc<W>> for RawWaker {
 fn raw_waker<W: Wake + Send + Sync + 'static>(waker: Arc<W>) -> RawWaker {
     // Increment the reference count of the arc to clone it.
     unsafe fn clone_waker<W: Wake + Send + Sync + 'static>(waker: *const ()) -> RawWaker {
-        unsafe { Arc::incr_strong_count(waker as *const W) };
+        unsafe { Arc::increment_strong_count(waker as *const W) };
         RawWaker::new(
             waker as *const (),
             &RawWakerVTable::new(clone_waker::<W>, wake::<W>, wake_by_ref::<W>, drop_waker::<W>),
@@ -81,7 +81,7 @@ fn raw_waker<W: Wake + Send + Sync + 'static>(waker: Arc<W>) -> RawWaker {
 
     // Decrement the reference count of the Arc on drop
     unsafe fn drop_waker<W: Wake + Send + Sync + 'static>(waker: *const ()) {
-        unsafe { Arc::decr_strong_count(waker as *const W) };
+        unsafe { Arc::decrement_strong_count(waker as *const W) };
     }
 
     RawWaker::new(

From fe4ac95cb858a7a26c94c2c236fe380448675a82 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Sat, 30 Jan 2021 21:08:30 +0100
Subject: [PATCH 2/2] Bump stable version of arc_mutate_strong_count

---
 library/alloc/src/sync.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/library/alloc/src/sync.rs b/library/alloc/src/sync.rs
index 1ff30ca610dbb..bfb3a8858ed3a 100644
--- a/library/alloc/src/sync.rs
+++ b/library/alloc/src/sync.rs
@@ -885,7 +885,7 @@ impl<T: ?Sized> Arc<T> {
     /// }
     /// ```
     #[inline]
-    #[stable(feature = "arc_mutate_strong_count", since = "1.50.0")]
+    #[stable(feature = "arc_mutate_strong_count", since = "1.51.0")]
     pub unsafe fn increment_strong_count(ptr: *const T) {
         // Retain Arc, but don't touch refcount by wrapping in ManuallyDrop
         let arc = unsafe { mem::ManuallyDrop::new(Arc::<T>::from_raw(ptr)) };
@@ -924,7 +924,7 @@ impl<T: ?Sized> Arc<T> {
     /// }
     /// ```
     #[inline]
-    #[stable(feature = "arc_mutate_strong_count", since = "1.50.0")]
+    #[stable(feature = "arc_mutate_strong_count", since = "1.51.0")]
     pub unsafe fn decrement_strong_count(ptr: *const T) {
         unsafe { mem::drop(Arc::from_raw(ptr)) };
     }